Method for influencing the propulsion of a motor vehicle that is driven by a driving motor

ABSTRACT

The invention relates to a method for influencing the propulsive power of a motor vehicle driven by a drive motor. In the method, an intervention variable (E), influencing the torque (M) of the drive motor ( 2 ), is ascertained. The intervention variable (E) is ascertained as a function of the wheel behavior of at least one wheel of the motor vehicle, and/or as a function of the motion of the motor vehicle. The drive motor ( 2 ) is acted upon with the intervention variable (E) to limit the propulsive power of the motor vehicle. In order to create, in the context of a motor vehicle with a slip control system, an easily manipulated, safe, and reliable capability for automatically detecting situations in which the driver desires a greater propulsive power and making a greater propulsive power available in those situations, it is proposed to evaluate a pedal variable (P) that describes the actuation of an accelerator pedal of the motor vehicle, or a limitation variable (B) that describes the number of limitations of driver stipulations resulting from the ascertaining of the intervention variable (E) within a definable time window. The intervention variable (E) is corrected, as a function of the pedal variable (P) or the limitation variable (B), toward a corresponding greater propulsive power.

[0001] The present invention relates to a method for influencing thepropulsive power of a motor vehicle driven by a drive motor. In themethod, an intervention variable influencing the torque of the drivemotor is ascertained. The intervention variable is transmitted as afunction of at least one wheel variable that describes the wheelbehavior of at least one wheel of the motor vehicle, and/or as afunction of at least one vehicle motion variable that describes themotion of the motor vehicle. To influence in limiting fashion thepropulsive power of the motor vehicle, the drive motor is acted uponwith the intervention variable.

[0002] The invention furthermore relates to a control unit for anapparatus for influencing the propulsive power of a motor vehicle drivenby a drive motor. The control device has means for determining at leastone wheel variable that describes the wheel behavior of at least onewheel of the motor vehicle. Alternatively or additionally, the controldevice has means for determining at least one vehicle motion variablethat describes the motion of the motor vehicle. The control devicefurthermore has means for determining an intervention variableinfluencing the torque of the drive motor. The intervention variable isdetermined as a function of the at least one wheel variable and/or theat least one vehicle motion variable. To influence in limiting fashionthe propulsive power of the motor vehicle, the drive motor is acted uponwith the intervention variable.

[0003] The present invention moreover relates to a memory element for acontrol device of an apparatus for influencing the propulsive power of amotor vehicle. The memory element is configured in particular as aread-only memory, as a random access memory, or as a flash memory. Acomputer program that is executable on a computing device, in particularon a microprocessor, is stored on the memory element. Lastly, theinvention also concerns such a computer program.

BACKGROUND INFORMATION

[0004] Methods and apparatuses for influencing the propulsive power of amotor vehicle are known, in many modifications, from the existing art.

[0005] German Patent 195 40 067 A1 discloses a method for controllingthe driving of multiple separately driven vehicle wheels of a motorvehicle. Upon the occurrence of drive slip at one of the drive wheels ofthe motor vehicle, the traction torque absent as a result of slip istransferred, up to a certain proportion, to the other drive wheel orwheels. This ensures that excessive drive torque is not transferred tothe drive wheel that is still gripping, since this would createincreased drive slip at that wheel as well. In particular, the driveslip of the drive wheel that is still gripping better is regulated to adrive slip setpoint that is set to a minimum setpoint which stillensures sufficient traction in every case.

[0006] In order to allow driving with an increased drive slip inspecific situations, in such situations the drive slip setpoint iscontinuously elevated. To detect these situations, the position of anaccelerator pedal of the motor vehicle is evaluated. If, in a situationwith an increased tendency toward drive slip, the driver does not letoff on the accelerator pedal but rather maintains its position or evenpresses it even further, this is interpreted as a desire to establish agreater drive slip at the drive wheels. The drive slip setpoints can bedefined uniformly for all drive wheels, or for individual wheels.

[0007] With the known method, the drive slip of a drive wheel of themotor vehicle is employed as the wheel variable. A drive slip setpointis ascertained, as the intervention variable, for one or more drivewheels of the motor vehicle.

[0008] A further example that may be cited of a method and an apparatusfor influencing the propulsive power of a motor vehicle is SAE Paper 870337, “ASR Traction Control—A Logical Extension of ABS.” With a driveslip control system of this kind (abbreviated ASR), the propulsive powerof a motor vehicle is adjusted as a function of the wheel slipascertained for the drive wheels. The propulsive power is adjusted insuch a way that the slip of the driven wheels does not exceed athreshold value defined for the drive wheels. The result of this measureis to ensure, in the drive context, stability of the vehicle as well assufficient traction.

[0009] The article “FDR—The Bosch vehicle dynamics control system”[FDR—Die Fahrdynamikregelung von Bosch], published inAutomobiltechnische Zeitschrift (ATZ) 96, 1994, Vol. 11, pages 674-689,discloses a slip control system in which the yaw rate of the motorvehicle is controlled. For this purpose, the deviation between asetpoint for the yaw rate and a measured value for the yaw rate isascertained. As a function of this system deviation, reference slipvalues are ascertained and are established with the aid of brakinginterventions and engine interventions. This type of slip control systemhas a higher-level controller for the yaw rate, and lower-levelcontrollers for a brake slip and a drive slip.

[0010] In addition to conventional drive slip control as described inSAE Paper 870 337, in which the wheel slip occurring at the drive wheelsis compared to threshold values, there is known from German Patent 19913 825 a method for adjusting the propulsive power in which anintervention variable is ascertained on the basis of characteristicsdiagrams. Provision is made for two characteristics diagrams. With afirst characteristics diagram, a first value for the interventionvariable is created as a function of a gradient of the slip and areference speed of the motor vehicle. With a second characteristicsdiagram, a second value for the intervention variable is created as afunction of a slip and the reference speed of the motor vehicle. Theintervention variable itself is then derived from the two values, forexample by addition. The propulsive power of the motor vehicle isadjusted as a function of the intervention value.

[0011] Also known, from German Patent 198 44 912, is an apparatus withwhich an intervention variable is ascertained as a function of atransverse acceleration variable and a variable that describes thebehavior over time of the transverse acceleration variable. Theintervention variable is ascertained on the basis of two characteristicsdiagrams: a first characteristics diagram for the transverseacceleration, and a second characteristics diagram for the variable thatdescribes the behavior over time of the transverse acceleration. Toinfluence the propulsive power, interventions are performed on the drivemotor of the motor vehicle as a function of the intervention variable.In the context of the methods and apparatuses discussed above forinfluencing the propulsive power of a motor vehicle, there aresituations with regard to drive slip in which a greater propulsive poweror elevated drive slip is desired.

[0012] One example that may be cited as a situation in which a greaterpropulsive power is desired is driving on an unconsolidated surface, forexample on gravel or in deep snow, or operating the motor vehicle withsnow chains, or off-road driving. When driving in deep snow, it mayhappen that the wheels of the motor vehicle “dig in” and the vehiclecomes to a stop. When the driver then attempts to start from rest insuch a situation, this will not be possible. Since the wheels have duginto the deep snow, they exhibit a great deal of drive slip whenattempting to start from rest. An ASR detects the slip and brakes thedriven wheels. The driver thus cannot generate sufficient propulsivepower to allow him or her to drive the motor vehicle out of its “dug-in”position.

[0013] For this reason, it is known in the context of ASR systems toarrange on the instrument panel a switch that can be actuated by thedriver. Actuation of the switch raises the slip thresholds of the ASRsystem. The result is that when the switch is pressed, an increasedpropulsive power can be established. This therefore makes it possiblefor the driver of a motor vehicle that is “dug in” in deep snow to drivethe vehicle back out of the deep snow by “rocking” it free.

[0014] A further situation in which greater propulsive power of themotor vehicle is desirable is, for example, a sporty driving style. As aresult of the interventions by a slip control system or an apparatussuch as the one known from German Patent 198 44 912, a sporty driver canfeel too limited. The slip control system or the aforementionedapparatus does ensure sufficient lateral stability for the vehicle incurves, but the result is that a driver cannot negotiate a curve withthe desired propulsive power that he or she has selected, since becausethe intervention variable is prepared as a function of the transverseacceleration and the change over time in the transverse acceleration,the intervention variable—and with it the propulsive power as well—islimited. The limitation is applied in such a way that in the context ofthe existing transverse acceleration and the change over time in thetransverse acceleration, and allowing for a certain safety factor, thedriving behavior of the motor vehicle is stable with a very highprobability. For a sporty driver, however, this can constitute alimitation.

[0015] The utilization, known from the existing art, of a switch tolower the drive slip thresholds also entails safety risks. If the driverforgets to release the switch again, and if the motor vehicle is nolonger in one of the situations described (e.g. in deep snow), then inother situations in which assistance by a slip control system (e.g. adrive slip control system or yaw rate control system) would benecessary, the stabilization of vehicle dynamics is absent orinsufficient.

[0016] It is therefore an object of the present invention, in thecontext of a motor vehicle with a slip control system, to create aneasily manipulated, safe, and reliable capability for automaticallydetecting situations in which the driver desires a greater propulsivepower and making a greater propulsive power available in thosesituations.

[0017] To achieve this object, the invention proposes, proceeding fromthe method of the kind cited initially for influencing the propulsivepower of a motor vehicle:

[0018] to ascertain a pedal variable that describes the actuation of anaccelerator pedal of the motor vehicle;

[0019] to compare a propulsive power corresponding to the pedal variableto a propulsive power corresponding to the intervention variable;

[0020] to correct the intervention variable, as a function of the pedalvariable, toward a corresponding greater propulsive power, if thepropulsive power corresponding to the pedal variable is greater than thepropulsive power corresponding to the intervention variable;

[0021] a correction variable being ascertained, for correction of theintervention variable, as a function of the pedal variable and therotation speed of the drive motor, and added to the interventionvariable; and

[0022] to act upon the drive motor with the corrected interventionvariable.

ADVANTAGES OF THE INVENTION

[0023] In order to recognize situations in which the driver desires agreater propulsive power, a pedal variable that describes the actuationof the accelerator pedal by the driver is ascertained. The pedalvariable is a measure of how much propulsive power the driver desires. Alarge pedal variable can be evaluated as an indication that the driverdesires a greater propulsive power. In the case in which the pedalvariable corresponds to a greater propulsive power than that establishedon the basis of the engine interventions performed as a function of theintervention variable, the intervention variable is modified, at leastas a function of the pedal variable, in such a way that a greaterpropulsive power is established.

[0024] For the case in which the pedal variable corresponds to a greaterpropulsive power than that established based on the engine interventionsperformed as a function of the intervention variable, the interventionvariable is to be modified in such a way that a greater propulsive poweris established. The modification of the intervention variable isachieved as follows: First, a characteristics diagram for which thepedal variable and a variable describing the rotation speed of theengine constitute input variables is evaluated. A correction variable isobtained as a function of the characteristics diagram and is added tothe intervention variable. This yields a corrected (and thus greater)intervention variable that results in a greater propulsive power. Thisgreater propulsive power is correlated with the driver's desire, whichcan be deduced from his or her actuation of the accelerator pedal.

[0025] The characteristics diagram is advantageously constructed in sucha way that the correction variable increases on the one hand with anincreasing pedal variable, and on the other hand with increasing enginespeed. The correction variable assumes maximum values when the pedalvariable is high and the engine speed is low. This dependence of thecorrection variable on the input variables of the characteristicsdiagram can be explained as follows: the propulsive power is to beincreased as a function of the pedal variable; consequently, thecorrection variable must become greater as the pedal variable increases.The rotation speed of the drive motor is taken account because theengine should be corrected less strongly with increasing rotation speedso as not to endanger the stability of the motor vehicle. The correctionvariable must therefore decrease with increasing engine speed.

[0026] The present invention encompasses two different concepts. In afirst concept, an intervention variable is ascertained as a function ofat least one wheel variable that describes the wheel behavior, andengine interventions are performed as a function of that interventionvariable to adjust the propulsive power of the vehicle. This concept canbe, for example, a conventional drive slip control system such as theone described in the aforementioned SAE Paper 870 337. With this driveslip control system, the slip present at the driven wheels is comparedto a corresponding threshold value. In this case, therefore, the wheelvariable corresponds to the wheel slip.

[0027] Furthermore, the first concept can also be a slip controlapparatus, for example as is known from Automobiltechnische Zeitschrift(ATZ) 96, loc. cit. In this case as well, the wheel variable correspondsto the wheel slip.

[0028] Alternatively, the first concept can also be based on theprocedure that is described in German Patent 199 13 825. The content ofthat patent application is hereby to be incorporated into theSpecification and to become part of the Specification. In thisapparatus, on the one hand the wheel slip itself and on the other handthe change over time in (or gradient of) the wheel slip are used as thewheel variable.

[0029] If the basis of the first concept is the procedure described inGerman Patent 199 13 825, then advantageously the pedal travel overwhich the pedal is deflected as a result of actuation by the driver issensed as the pedal variable. Alternatively, the angle of the pedaldeflection can also be sensed. A corresponding pedal variable is alsoevaluated in the slip control systems that are described in theaforementioned SAE Paper, loc. cit. and the ATZ article, loc. cit.Lastly, a variable that describes the change over time in the pedaltravel, i.e. the pedal travel gradient, can also be sensed as the pedalvariable.

[0030] In the context of a second concept, an intervention variable isascertained as a function of at least one vehicle motion variable thatdescribes the vehicle motion, and engine interventions to adjust thepropulsive power are performed as a function of that interventionvariable. A concept of this kind is described, for example, in GermanPatent 198 44 912. The content of that patent application is hereby tobe incorporated into the Specification and to become part of theSpecification. This apparatus contains means with which a transverseacceleration variable, which describes the transverse accelerationacting on the vehicle, is sensed. The apparatus moreover contains meanswith which a variable that describes the behavior over time of thetransverse acceleration variable is ascertained. As a function of thetransverse acceleration variable and the variable that describes thebehavior over time of the transverse acceleration variable, anintervention variable is ascertained using characteristics diagrams.Engine interventions are performed to influence the propulsive power,the engine interventions being performed as a function of theintervention variable.

[0031] In this concept, on the one hand the transverse accelerationvariable itself and on the other hand its derivation over time areprocessed as vehicle motion variables. More precisely, the interventionvariable is ascertained as a function of the transverse acceleration andthe change over time in the transverse acceleration. With this concept,sufficient lateral stability of the vehicle in curves can be ensured.

[0032] For the second concept as well, the method according to thepresent invention provides for correcting the intervention variable asapplicable, as a function of the pedal variable, toward a correspondinggreater propulsive power. In this case the method according to thepresent invention corresponds to a driver type recognition system, withwhich the sporty driver is recognized and with which, upon recognitionof a sporty driver, the propulsive power is correspondingly increased.

[0033] As is evident from the discussion above, a certain “learning”phase is initially necessary, in which the system determines theparticular driver type on the basis of the variables that are present.As soon as it is apparent that the driver is a sporty one, a change inthe intervention variable toward greater propulsive power is authorized.

[0034] According to an advantageous development of the presentinvention, it is proposed that before correction of the interventionvariable, a check be made as to whether the pedal variable is greaterthan a definable first threshold value; and the intervention variable isnot corrected if the pedal variable is less than or equal to the firstthreshold value.

[0035] Alternatively or additionally, according to another advantageousdevelopment of the present invention it is proposed that beforecorrection of the intervention variable, a check be made as to whether atransverse acceleration of the motor vehicle is less than a definablesecond threshold value; and the intervention variable is not correctedif the transverse acceleration is greater than or equal to the secondthreshold value. Taking the transverse acceleration into accounteliminates those instances in which the increase in propulsive powerwould result in an instability of the vehicle in the vehicle'stransverse direction. In the case described above of “rocking” a motorvehicle loose when it has become stuck in deep snow, usually very littleor no transverse acceleration occurs, since the vehicle cannot movelaterally. Such a situation is recognized by the plausibility query andmakes possible an increase in propulsive power.

[0036] These two developments thus include a plausibility check of thepedal variable and of the transverse acceleration of the motor vehicle.The intervention variable is corrected only if the pedal variable isequal to or greater than the first threshold value and/or the transverseacceleration is less than or equal to the second threshold value.

[0037] As a further way of achieving the object of the presentinvention, it is proposed, proceeding from the method of the kind citedinitially:

[0038] to ascertain a limitation variable that describes the number oflimitations of driver stipulations resulting from the ascertaining ofthe intervention variable within a definable time window;

[0039] to correct the intervention variable as a function of thelimitation variable toward a corresponding greater propulsive power ifthe limitation variable exceeds a definable third threshold value; and

[0040] to act upon the drive motor with the corrected interventionvariable.

[0041] As an alternative to the evaluation of the pedal variable, it isalso possible to evaluate how often the driver stipulations are limited.What is ascertained, therefore, is how often a lesser propulsive powerthan that which the driver would actually like to achieve is establishedas a result of ascertaining the intervention variable as a function ofthe wheel variable or the vehicle motion variable. This examination withregard to the frequency of limitation is advantageously made within adefinable time window. In addition, it is an advantageous possibility toevaluate changes in the wheel rotation speeds in terms of the driver'sacceleration behavior (in which case the non-driven wheels areconsidered) or in terms of his or her deceleration behavior (in whichcase the wheels without brake slip control are considered).

[0042] The nature of the intervention variable influencing the deliveredtorque depends on a variety of factors. On the one hand, for differentdrive motors it is possible also to use different intervention variableswith which the torque delivered by the drive motor is influenced. Forone and the same drive motor there may moreover be differentintervention variables with which the torque delivered by the drivemotor can be influenced.

[0043] According to a preferred embodiment of the present invention, itis proposed that in the context of a drive motor configured as aninternal combustion engine, a fuel quantity to be injected into anintake manifold or into a combustion chamber of the internal combustionengine be employed as the intervention variable influencing thedelivered torque.

[0044] According to a further preferred embodiment of the presentinvention, it is proposed that in the context of a drive motorconfigured as an internal combustion engine, a point in time for theinjection of fuel into an intake manifold or into a combustion chamberof the internal combustion engine be employed as the interventionvariable influencing the delivered torque.

[0045] According to yet another preferred embodiment of the presentinvention, it is proposed that in the context of a drive motorconfigured as an internal combustion engine, a point in time forignition of a fuel-air mixture present in a combustion chamber of theinternal combustion engine be employed as the intervention variableinfluencing the delivered torque.

[0046] It is furthermore proposed that in the context of a drive motorconfigured as an internal combustion engine, an angle of a throttlevalve of the internal combustion engine be employed as the interventionvariable influencing the delivered torque.

[0047] Lastly, it is proposed that in the context of a drive motorconfigured as an electric motor, a current or a voltage be employed asthe intervention variable influencing the delivered torque.

[0048] As a further way of achieving the object of the presentinvention, it is proposed, proceeding from the control device of thekind cited initially, that means for carrying out the method accordingto the present invention be implemented in the control device.

[0049] Particularly significant is the implementation of the methodaccording to the present invention in the form of a memory element thatis provided for a control device of a vehicle dynamics control system ofa motor vehicle. In this context, a computer program that is executableon a computing device, in particular on a microprocessor, and issuitable for carrying out the method according to the present invention,is stored on the memory element. In this case, therefore, the inventionis realized by way of a computer program stored on the memory element,so that this memory element equipped with the computer programconstitutes the invention in the same way as the method for whoseperformance the computer program is suitable. An electrical memorymedium, for example a read-only memory, a random access memory, or aflash memory, can, in particular, be used as the memory element.

[0050] Lastly, the invention also concerns a computer program that issuitable for carrying out the method according to the present inventionwhen it executes on a computing device, in particular on amicroprocessor. It is particularly preferred in this context if thecomputer program is stored on a memory element, in particular on a flashmemory.

DRAWINGS

[0051] Further features, possible applications, and advantages of theinvention are evident from the description below of exemplaryembodiments of the invention, which are depicted in the drawings. Allthe features described or depicted constitute, of themselves or in anycombination, the subject matter of the invention, irrespective of theirsummarization in the claims or their internal references, andirrespective of their presentation or depiction in the specification orthe drawings. In the drawings:

[0052]FIG. 1 shows a first preferred exemplary embodiment of a methodaccording to the present invention;

[0053]FIG. 2 shows a second preferred exemplary embodiment of a methodaccording to the present invention;

[0054]FIG. 3 shows a second preferred exemplary embodiment of a methodaccording to the present invention; and

[0055]FIG. 4 shows a characteristics diagram for ascertaining acorrection variable for correction, according to the present invention,of a torque-influencing intervention variable.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0056] Regarding the description of FIG. 1, what will be discussed firstis a drive slip control system of a motor vehicle like that described inSAE Paper 870 337. In this, an intervention variable E influencingtorque M of a drive motor 2 of the motor vehicle is ascertained as afunction of a wheel variable R. A slip of a drive wheel of the motorvehicle is employed as wheel variable R. Intervention variable E isascertained in a processing unit 1 as a function of a deviation betweenthe ascertained wheel slip R and an associated threshold value R_schw.Intervention variable E corresponds to or describes the propulsive powerthat is to be established. When drive motor 2 of the motor vehicle isacted upon with intervention variable E ascertained on the basis of thedrive slip control system, the motor vehicle can start from rest oraccelerate without spinning its wheels.

[0057] In the context of a drive motor 2 configured as a diesel engine,intervention variable E is the fuel quantity to be injected. In thecontext of internal combustion engines in general, an injection time, anignition time (so-called ignition angle), or a throttle valve angle canbe employed as intervention variable E.

[0058] With the method depicted in FIG. 1, it is possible to recognizeautomatically a situation in which the driver of the motor vehicledesires a higher propulsive power. For that purpose, a pedal variable Pis analyzed. Pedal variable P can be the travel of an accelerator pedalor the gradient of the accelerator pedal travel. In addition, theduration or intensity of the accelerator pedal actuation can also beincorporated into pedal variable P. A propulsive power V_E correspondingto intervention variable E is calculated in a processing unit 3. Apropulsive power V_P corresponding to pedal variable P is similarlydetermined in a processing unit 4. In a comparison unit 5, a comparisonis made between propulsive power V_E that has been set and the desiredpropulsive power V_P. If propulsive power V_P corresponding to pedalvariable P is greater than propulsive power V_E corresponding tointervention variable E, intervention variable E is corrected, as afunction of pedal variable P, toward a corresponding greater propulsivepower.

[0059] In order to correct intervention variable E, a correctionvariable K is ascertained and is added to intervention variable E.Correction variable K is ascertained on the basis of a characteristicsdiagram 6 as a function of rotation speed n of drive motor 2 and pedalvariable P. A corresponding characteristics diagram 6 is depicted inFIG. 3. Correction value K is present at one input of a switching unit7. The value “0” is present at the other input. Switching unit 7 isactuated by an output signal of comparison unit 5. If propulsive powerV_E is greater than or equal to propulsive power V_P, switching unit 7does not switch, and the value “0” is added to intervention variable E.Otherwise switching unit 7 does switch, and correction variable K isadded to intervention variable E. Drive motor 2 is acted upon with thesum of intervention variable E and correction variable K, therebyachieving a greater propulsive power for the motor vehicle.

[0060] In the context of a slip control system such as that described inthe ATZ article cited above, intervention variable E is ascertained as afunction of the deviation between wheel slip R ascertained for a wheeland the wheel slip setpoint existing for that wheel.

[0061] A further exemplary embodiment of the method according to thepresent invention will be described below with reference to FIG. 2. Inthe context of an apparatus for influencing the propulsive power of amotor vehicle as described in German Patent 199 13 825, firstly a firstvalue E1 for intervention variable E is ascertained in a firstprocessing unit 8 as a function of the change over time in wheel slip Rand speed V of the vehicle. A second value E2 for intervention variableE is ascertained in a second processing unit 9 as a function of wheelslip R and vehicle speed V. First value E1 and second value E2 are addedto intervention value E. If pedal variable P is greater than acorresponding threshold value P_schw (comparison unit 10), and iftransverse acceleration QB acting on the vehicle is less than acorresponding threshold value QB_schw (comparison unit 11), a correctionvariable K for intervention variable E is ascertained. Correctionvariable K is ascertained, as already mentioned, with the aid ofcharacteristics diagram 6. Correction variable K is added tointervention variable E. This addition implements a traction assistanceaction. The propulsive power of the vehicle is adjusted as a function ofintervention variable E corrected in this fashion. This propulsive poweris greater than propulsive power V_E present before the tractionassistance action.

[0062] In the context of a method for influencing the propulsive powerof a vehicle as described in German Patent 198 44 912 (but not depictedin the Figures), intervention variable E is ascertained as a function ofa transverse acceleration variable QB and a variable dQB/dt whichdescribes the behavior over time of transverse acceleration QB.Intervention variable E is ascertained on the basis of twocharacteristics diagrams: a first characteristics diagram for transverseacceleration QB, and a second characteristics diagram for variabledQB/dt which describes the behavior over time of transverse accelerationQB. To influence the propulsive power, interventions are made in drivemotor 2 of the motor vehicle as a function of intervention variable E.

[0063]FIG. 3 depicts a further preferred exemplary embodiment of thepresent invention. In this, a situation in which a greater propulsivepower is desired by the driver of the motor vehicle is ascertained byevaluating a limitation variable B. Limitation variable B describes thenumber of limitations of driver stipulations resulting from theascertaining of intervention variable E within a definable time window.If limitation variable B exceeds a definable threshold value B_schw,intervention variable E is corrected toward a corresponding greaterpropulsive power. The comparison is performed in a comparison unit 12.For correction, correction variable K ascertained by characteristicsdiagram 6 is added to intervention variable E. Drive motor 2 is actedupon with the corrected intervention variable, i.e. the sum ofcorrection variable K and intervention variable E that was ascertained.

[0064] Once correction variable K has been ascertained, it isconceivable to perform a plausibility query (which is not, however,depicted in the Figures). For example, a check can be made as to whethertransverse acceleration QB acting on the vehicle is less than acorresponding threshold value QB_schw, whether pedal variable P isgreater than a corresponding threshold value P_schw, and whetherrotation speed n of drive motor 2 is less than a corresponding thresholdvalue n_schw. Correction variable K is added to intervention variable Eonly if all the plausibility queries are met.

[0065]FIG. 4 depicts the profile of characteristics diagram 6 forascertaining correction variable K from pedal variable P and therotation speed of drive motor 2. Characteristics diagram 6 isconstructed in such a way that correction variable K increases on theone hand with increasing pedal variable P and on the other hand withincreasing engine speed n. Correction variable K assumes maximum valueswhen pedal variable P is large and engine speed n is low. Thisdependence of correction variable K on input variables P, n ofcharacteristics diagram 6 can be explained as follows: propulsive poweris to be increased as a function of pedal variable p; consequently thecorrection variable must become greater with increasing pedal variableP. Rotation speed n of drive motor 2 is taken into account because motor2 should be corrected less strongly with increasing rotation speed n soas not to endanger the stability of the motor vehicle.

[0066] What is considered in the present case is a diesel engine whoseintervention variable E is the fuel quantity to be injected (in units ofmm³). Correction variable K thus also uses the unit of mm³. Incharacteristics diagram 6 considered here, correction variable K rangesfrom 0 to 8 mm³. Rotation speed n ranges from 1500 rpm to 4600 rpm.Pedal variable P ranges from 50% to 100%.

What is claimed is:
 1. A method for influencing the propulsive power ofa motor vehicle driven by a drive motor (2), in which there isascertained, as a function of at least one wheel variable (R, dR/dt)that describes the wheel behavior of at least one wheel of the motorvehicle, and/or as a function of at least one vehicle motion variable(V, QB, dQB/dt) that describes the motion of the motor vehicle, anintervention variable (E), influencing the torque (M) of the drive motor(2), with which the drive motor (2) is acted upon to influence inlimiting fashion the propulsive power of the motor vehicle, wherein apedal variable (P) that describes the actuation of an accelerator pedalof the motor vehicle is ascertained; a propulsive power corresponding tothe pedal variable (P) is compared to a propulsive power correspondingto the intervention variable (E); the intervention variable (E) iscorrected, as a function of the pedal variable (P), toward acorresponding greater propulsive power, if the propulsive power (V_P)corresponding to the pedal variable (P) is greater than the propulsivepower (V_E) corresponding to the intervention variable (E); a correctionvariable (K) being ascertained, for correction of the interventionvariable (E), as a function of the pedal variable (P) and the rotationspeed (n) of the drive motor (2), and added to the intervention variable(E); and the drive motor (2) is acted upon with the correctedintervention variable.
 2. The method as defined in claim 1, whereinbefore correction of the intervention variable (E), a check is made asto whether the pedal variable (P) is greater than a definable firstthreshold value (P_schw); and the intervention variable (E) is notcorrected if the pedal variable (P) is less than or equal to the firstthreshold value (P_schw).
 3. The method as defined in claim 1 or 2,wherein before correction of the intervention variable (E), a check ismade as to whether a transverse acceleration (QB) of the motor vehicleis less than a definable second threshold value (QB_schw); and theintervention variable (E) is not corrected if the transverseacceleration (QB) is greater than or equal to the second threshold value(QB_schw).
 4. The method as defined in one of claims 1 through 3,wherein the correction variable (K) is ascertained on the basis of acharacteristics diagram (6).
 5. A method for influencing the propulsivepower of a motor vehicle driven by a drive motor (2), in which there isascertained, as a function of at least one wheel variable (R, dR/dt)that describes the wheel behavior of at least one wheel of the motorvehicle, and/or as a function of at least one vehicle motion variable(V, QB, dQB/dt) that describes the motion of the motor vehicle, anintervention variable (E), influencing the torque (M) of the drive motor(2), with which the drive motor (2) is acted upon to influence inlimiting fashion the propulsive power of the motor vehicle, wherein alimitation variable (B) is ascertained that describes the number oflimitations of driver stipulations resulting from the ascertaining ofthe intervention variable (E) within a definable time window; theintervention variable (E) is corrected, as a function of the limitationvariable (B), toward a corresponding greater propulsive power if thelimitation variable (B) exceeds a definable third threshold value(B_schw); and the drive motor (2) is acted upon with the correctedintervention variable.
 6. The method as defined in one of claims 1through 5, wherein in the context of a drive motor (2) configured as aninternal combustion engine, a fuel quantity to be injected into anintake manifold or into a combustion chamber of the internal combustionengine is employed as the intervention variable (E) influencing thedelivered torque (M).
 7. The method as defined in one of claims 1through 6, wherein in the context of a drive motor (2) configured as aninternal combustion engine, a point in time for the injection of fuelinto an intake manifold or into a combustion chamber of the internalcombustion engine is employed as the intervention variable (E)influencing the delivered torque (M).
 8. The method as defined in one ofclaims 1 through 7, wherein in the context of a drive motor (2)configured as an internal combustion engine, a point in time forignition of a fuel-air mixture present in a combustion chamber of theinternal combustion engine is employed as the intervention variable (E)influencing the delivered torque (M).
 9. The method as defined in one ofclaims 1 through 8, wherein in the context of a drive motor (2)configured as an internal combustion engine, an angle of a throttlevalve of the internal combustion engine is employed as the interventionvariable (E) influencing the delivered torque (M).
 10. The method asdefined in one of claims 1 through 6, wherein in the context of a drivemotor (2) configured as an electric motor, a current or a voltage isemployed as the intervention variable (E) influencing the deliveredtorque (M).
 11. A control device for an apparatus for influencing thepropulsive power of a motor vehicle driven by a drive motor (2), havingmeans for determining at least one wheel variable (R, dR/dt) thatdescribes the wheel behavior of at least one wheel of the motor vehicle;and/or means for determining at least one vehicle motion variable (V,QB, dQB/dt) that describes the motion of the motor vehicle; and meansfor determining an intervention variable (E), influencing the torque (M)of the drive motor (2), as a function of the at least one wheel variable(R, dR/dt) and/or the at least one vehicle motion variable (V, QB,dQB/dt), the drive motor (2) being acted upon with the interventionvariable (E) to influence in limiting fashion the propulsive power ofthe motor vehicle, wherein means for carrying out a method as defined inone of claims 1 through 10 are implemented in the control device.
 12. Amemory element, in particular read-only memory, random access memory, orflash memory, for a control device of an apparatus for influencing thepropulsive power of a motor vehicle, on which is stored a computerprogram that is executable on a computing device, in particular on amicroprocessor, and is suitable for carrying out a method as defined inone of claims 1 through
 10. 13. A computer program, wherein the computerprogram is suitable for carrying out a method as defined in one ofclaims 1 through 10 when it executes on a computing device, inparticular on a microprocessor.
 14. The computer program as defined inclaim 13, wherein the computer program is stored on a memory element, inparticular on a flash memory.